I bought a set of roof rails for my new Freelander 2 from 4×4 Accessories & Tyres Limited
I fitted them following a downloaded set of instructions from LR for most of the job.
However, on close inspection I could see no reason for making the rear two holes in the plastic insert on each side larger, and so there was no reason to remove the long lengths of plastic molding from the car.
The metal inserts which act as vertical spacers are stepped, the top diameter being 24mm, the bottom (as fitted) is approximately 10mm. This last being the diameter of the existing hole in the plastic insert in the roof channel.
If the threaded hole in the roof does not line up exactly with this hole I can see the need to make the hole bigger. The holes in the roof rail supports through which the bolts pass are large enough to accommodate a fair degree of misalignment.
Indeed one of the holes did not match up with the hole in the molding so I made a curved bit to fit an old soldering gun and melted out a crescent shape.
Even if all of the holes had needed adjustment in this way it would still have been easier / simpler than removing, drilling and re sticking the two inserts.
The single front pillar bolts do require a 24mm hole at the + spots, so this part does need the moldings to be lifted, both for drilling and for removal of the existing bolts.
This was the hardest part of the whole job, due to the low profile of the bolt and the resulting difficulty in getting a socket to grip.
To reduce drag I have not yet fitted the cross bar. I have blanked the four crossbar holes with silicone mastic and roofing bolts. I carry the cross bar, proper bolts and a flexible driver with suitable bits in the car in case I need to carry anything.

We had quite a game fitting the crossbar and had to use a flexi extension and wobble bars to get the bolts in.

I’m still not convinced the roof bars are going to stay on. They make too much wind noise for my liking. Seriously thinking of taking them off and getting some Thule bars for when I do need the roof box.

Additional to my original fitting comment:
I have just spent an hour failing to fit the cross bar (for practice) as I’d intended to leave it off until needed at the DIY store.
I’m glad I decided to practice. I eventually fitted them by taking the rails off the vehicle, bolting the crossbar on to the rails then refitting the rails/bar structure as one.
Easier than the original fiddle but, still not great.
I had to get the rail bolts just threaded in on one side, then I used a long sash cramp to put a bit of compression, and therefore a slight bow, into the cross bar. This allowed the rail bolt nearest the crossbar to be started into the thread and from there on all 6 bolts were tightened to spec..